Our expression and localization studies of PbSERA4 using a specific antibody and a parasite line in which the endogenously encoded protein is fluorescently tagged show that PbSERA4 is expressed in blood-stage and late-liver-stage Plasmodium. Previous studies demonstrated that SERA family members in P. falciparum and P. berghei are proteolytically processed to their active form [10, 18, 31, 33], and our data demonstrate that PbSERA4 appears also to be proteolytically processed during infection. The gene discussed is PHGDH; the disease is infection.